SUMMARY
This research at PT Inspira Multi Karya, a furniture-producing company where most activities are done manually. Lot of physical activities may cause workers to suffer from musculoskeletal disorders (MSD) whose symptom are feelings of pain and discomfort in muscles. Therefore, this study aims to see the relationship between physical activity and MSD complaints and also the sensitivity of tools for improving work systems. Tools to measure physical activity used the Global Physical Activity Questionnaire and tools to measure MSD complaints used Rapid Upper Limb Assessment and Nordic Body Map. The observed operators total 15 people, working at 6 different workstations with different postures. Interesting findings show that there is a significant correlation between physical activity and complaints of musculoskeletal disorders. When physical activity increases, MSD complaints also increase. The research findings show that 60% of operators have a work posture that needs immediate attention to be corrected because it has a high chance of causing MSDs complaints. The body parts that experience the biggest subjective complaints of MSD are the left calf, waist, forearm, back, right hand, and right calf. Mainly urgent repairs need to be done on the press machine (operators work in static postures for more than 10 minutes, with a lifting load of 2 kg-10 kg). Improvements were made by increasing the height of the base of the press machine as high as 50 cm. The improvement of work system can reduce MSD score from 7 to 4 in RULA scale. A comparison of the three methods shows that the RULA is the most suitable methods for analysing MSD in furniture factories because it can analyse upper/lower extreme body postures, both in static and dynamic postures, with repetitive activities, with loads, and carried out for a long time.